Hi SSPVinyl,
I have seen the blade holder cause similar missed cuts in the past, hence my guess that it may be the culprit here. I see that you have called and spoken with our tech support folks and that they recommended switching out the blade holder and cleaning the cutting head, so hopefully that fixes the issues you are having.
Please feel free to contact myself or tech support if that doesn’t fix the issue and we can do some additional troubleshooting.
Best regards,
Phil Johnson
Summa, Inc.